// Test generation with null thumbnail ID
        assertFalse(thumbnailGenerator.generate(null, tempOutputFile));
    }

    public void test_generate_withEmptyThumbnailId() {
        // Test generation with empty thumbnail ID
        assertFalse(thumbnailGenerator.generate("", tempOutputFile));
    }

    public void test_generate_withNullOutputFile() {
        // Test generation with null output file

    StringSubscriber s2 = new StringSubscriber();
    ObjectSubscriber o1 = new ObjectSubscriber();

    Iterator<Subscriber> empty = registry.getSubscribers("");
    assertFalse(empty.hasNext());

    empty = registry.getSubscribers("");

    registry.register(s1);
    assertFalse(empty.hasNext());

    Iterator<Subscriber> one = registry.getSubscribers("");
    assertEquals(s1, one.next().target);

                               aria-controls="listSearchForm"><i class="fas fa-search" aria-hidden="true"></i></a>
                            <div class="collapse <c:if test="${!empty name || !empty paths || !empty description}">show</c:if>" id="listSearchForm">
                                <la:form action="/admin/fileconfig/">
                                    <div class="form-group row">

            public List<DataConfig> getAllDataConfigList() {
                return new ArrayList<>(); // Always return empty for fast tests
            }

            @Override
            public List<DataConfig> getDataConfigListByIds(List<String> configIdList) {
                return new ArrayList<>(); // Always return empty for fast tests
            }

            public String store(String sessionId, DataConfig dataConfig) {

     */
    public OptionalEntity<StemmerOverrideFile> getStemmerOverrideFile(final String dictId) {
        return dictionaryManager.getDictionaryFile(dictId)
                .filter(StemmerOverrideFile.class::isInstance)
                .map(file -> OptionalEntity.of((StemmerOverrideFile) file))
                .orElse(OptionalEntity.empty());
    }

    /**

   * @throws NullPointerException if any element in the stream is {@code null}.
   * @return {@code Optional.of(onlyElement)} if the stream has exactly one element (must not be
   *     {@code null}) and returns {@code Optional.empty()} if it has none.
   */
  @SuppressWarnings("unchecked")
  public static <T> Collector<T, ?, Optional<T>> toOptional() {
    return (Collector) TO_OPTIONAL;
  }

        () -> EnumHashBiMap.create(Collections.<Currency, String>emptyMap()));

    /* Map can be empty if it's an EnumHashBiMap. */
    Map<Currency, String> emptyBimap = EnumHashBiMap.create(Currency.class);
    bimap = EnumHashBiMap.create(emptyBimap);
    assertTrue(bimap.isEmpty());

    /* Map can be empty if it's an EnumBiMap. */
    Map<Currency, Country> emptyBimap2 = EnumBiMap.create(Currency.class, Country.class);

 * @since 4.0.0
 */
@Experimental
public interface Interpolator extends Service {

    /**
     * Interpolates the values in the given map using the provided callback function.
     * This method defaults to setting empty strings for unresolved placeholders.
     *
     * @param properties The map containing key-value pairs to be interpolated.
     * @param callback The function to resolve variable values not found in the map.
     */

  /**
   * Creates an empty {@code ArrayBlockingQueue} with the given (fixed) capacity and nonfair access
   * policy.
   */
  @J2ktIncompatible
  @GwtIncompatible // ArrayBlockingQueue
  public static <E> ArrayBlockingQueue<E> newArrayBlockingQueue(int capacity) {
    return new ArrayBlockingQueue<>(capacity);
  }

  // ArrayDeque

  /**
   * Creates an empty {@code ArrayDeque}.
   *
   * @since 12.0

  }

  @GwtIncompatible // ObjectArrays.newArray(Class, int)
  public void testNewArray_fromClass_empty() {
    String[] empty = ObjectArrays.newArray(String.class, 0);
    assertEquals(String[].class, empty.getClass());
    assertThat(empty).isEmpty();
  }

  @GwtIncompatible // ObjectArrays.newArray(Class, int)
  public void testNewArray_fromClass_nonempty() {